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High-throughput bioprinted 3D cultures for probing host–pathogen interactions in bioinspired microenvironments
No full textThis article was originally published in RSC Applied Polymers. The version of record is available at: https://doi.org/10.1039/D5LP00285K
This Open Access Article is licensed under a Creative Commons Attribution-Non Commercial 3.0 Unported Licence https://creativecommons.org/licenses/by-nc/3.0/The microenvironment of immune cells is an important regulator of their function and fate. Three-dimensional (3D) culture systems provide opportunities for probing immune cell responses to invading pathogens in microenvironments with biophysical and biochemical properties inspired by human tissues. Yet, the low throughput and manual preparation of many 3D culture models present challenges for translation of assays and their broad and accessible use for studying host–pathogen interactions. To address this, we established a high-throughput macrophage-bacteria co-culture model that mimics lung tissue stiffness across healthy and diseased conditions. Using bioprinting, human THP-1 monocytes were encapsulated and differentiated into macrophages within synthetic extracellular matrices (ECMs) fabricated with well-defined polymer and peptide bioinks in a 96-well plate format. Macrophages retained viability and displayed immunocompetence, including phenotype, phagocytosis, and response to stimuli. Macrophages in fibrosis-inspired ‘stiffer’ (storage modulus (G′) ∼4.8 kPa) microenvironments exhibited higher basal expression of both inflammation and traditional fibrosis associated genes compared to more compliant (G′ ∼1.1 kPa) synthetic ECMs inspired by healthy lung microenvironments. We applied our model 3D cultures to study immune response to invasion of a bacterial pathogen implicated in hospital born lung infections and mortality, Pseudomonas aeruginosa. Macrophages exhibited differential responses to P. aeruginosa in stiff microenvironments, with decreased cytokine secretion of IL-6 and IL-1β and elevated IL-10 and TNF-α compared to healthy compliant microenvironments, suggesting that microenvironment properties may shape initial immune responses. This high-throughput, accessible controlled platform provides opportunities for understanding human host–pathogen interactions and a foundation for identifying therapeutic strategies for bacterial infections in well-defined physiologically relevant microenvironments.This work was supported by grants for related work from a National Institutes of Health (NIH) Director's New Innovator Award with grant number DP2HL152424 (Kloxin), a NIH National Institute of General Medicine (NIGMS) Award with grant number R35GM142866A (Fromen), Delaware Bioscience Center for Advanced Technology grant (12A00448), and Defense Threat Reduction Agency (DTRA) CBM (HDTRA1448297). Additionally, the authors acknowledge the use of facilities and instrumentation supported by the National Science Foundation (NSF) through the University of Delaware Materials Research Science and Engineering Center (DMR-2011824) and the NIH National Institute of General Medical Sciences (NIGMS) through the Delaware COBRE (P20GM104316). Access to microscopy and analysis software within Delaware Biotechnology Institute (DBI) BioImaging was supported by the Institutional Development Award (IDeA) from the NIH NIGMS under grant number P20GM103446, as well as NIGMS (P20 GM139760) and the State of Delaware. The authors thank the DBI Bioimaging Core, specifically Jeffrey Caplan and Chandran Sabanayagam, for training and assistance in imaging and image analysis of bacterial phagocytosis and DBI DNA Sequencing Core and Genotyping Core, specifically Brewster Kingham and Mark Shaw. The authors thank Claire Lois for support of bacteria cultures and Inventia Life Science for use and support of the RASTRUMTM bioprinter, especially Dwayne Dexter and Whitney Symons. Additional student support was obtained from the Collins fellowship and NSF Graduate Research Fellowship Program (GRFP) Award number 1940700 (Graf) and NIH Chemistry-Biology Interface program supported by the NIGMS of the NIH (T32GM133395) (Moore). The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH, NSF, or DTRA CBM. Fig. 1A, 3A, 4A, and 5A were created using BioRender.com
Assessment of seabed munition mobility induced by propeller-generated turbulence
No full textPuleo, Jack A.Van Buren, TylerIn the years prior to the contemporary environmental movement, navies around the world dumped unused munitions overboard for disposal. In 1972, the London Convention banned many pollutants, including munitions. Half a century since, these potentially live munitions can come onshore or be uncovered by erosion, posing serious risks to the public. Among the mechanisms driving munitions mobility, this study investigates the influence of propeller generated turbulence on munitions transport. The experiment used a large pool with a sediment bed and a proud munition model (also referred to as target). An overhead outboard motor was used to simulate vessel propeller wash. Results showed munition density was a parameter governing target stability under propeller-generated flows. Targets constructed to emulate high density conventional munitions demonstrated strong resistance to displacement by not exhibiting movement under tested flow regimes. In contrast, movement was observed only when the targets were configured to be less than half as dense as conventional ordnance. Detailed measurements further established that the magnitude of target displacement was governed by density and sensitive to spatial proximity to the propeller; targets positioned near the point of maximum jet velocity experienced substantially larger mobilization. The patterns affirm that, in deep-water scenarios where propeller-induced turbulence dissipates rapidly and munitions remain dense, the overall risk of large-scale munition migration is low. Nevertheless, there is a heightened vulnerability for less dense munitions or scenarios characterized by high-energy, confined settings—such as navigation channels and high traffic port facilities—where persistence of strong, localized flows can present a mobilization threat. The ability to predict munition movement, combined with general historical disposal data are crucial to predict when/where expected munitions may arise. Local authorities can then exclude the populace until ordnance experts can properly dispose of them in a safe and formal process, akin to the Iron Harvest in northern France.Department of Civil, Construction and Environmental EngineeringM.S.Ocean Engineering Progra
A multi-approach to the removal and analysis of micro-/nano- plastics (MNPs)
No full textWu, ChangqingThe wide occurrence of micro- and nano plastics (MNPs) in food, water, soil and air has caused increasing concerns on potential human health impacts and environmental pollution. Accurate identification and efficient elimination of these particles continue to pose difficulties owing to their diminutive size, chemical heterogeneity, and interactions within intricate matrices. This work explored a multi-modal methodology for the detection and removal of MNPs in liquids. A plastic-free, chemically densified carbon nanotube (DCN) membrane was assessed for its effectiveness in filtering MNPs and foodborne pathogens, using the fluorescent polystyrene (PS) particles and Escherichia coli and Listeria innocua as model targets in the studies. Additionally, our collaboration with Dr. Ruogu Tang and Dr. Juzhong Tan explored the use of biochar for removing MNPs. Both DCN and biochar filters exhibited excellent removal of MNPs, with biochar displaying a higher efficacy on removing bigger aggregated particles in HPLC water. DCN membranes consistently demonstrated superior removal of MNPs, with 0.95 and 2.1 µm particles typically decreased by over 90%. Biochar filters exhibited comparable performance for submicron particles (0.1 and 0.5 µm) and demonstrated a pronounced effectiveness for bigger MNPs, with removal rates for aggregated MNPs (2 µm) often surpassing 85–90%. Test solutions, comprising HPLC water, bottled water, and apple juice, were added with model MNPs and treated in vitro digestion, simulating stomach and intestinal conditions. MNPs in the solutions before and after digestion were evaluated by different methods. ☐ The quantitative and qualitative evaluation of MNPs was performed utilizing Nile Red fluorescence staining with fluorescence imaging or reading, Dynamic Light Scattering (DLS), Nanoparticle Tracking Analysis (NTA), and Scanning Electron Microscopy (SEM). In this phase of the study, commercial 0.5 and 2 µm MNPs (fluorescently labeled and non-labeled), alongside with various pretreatment methodologies (in vitro or chemical digestion, matrix-specific background correction rinsing, and centrifugation were added into HPLC water, bottled water and apple juice, and then quantified by the various methods. Nile Red staining of non-labeled PS particles generated fluorescence signals that were dependent on MNPs concentration and size, facilitating the creation of calibration curves for both 0.5 and 2 µm MNPs. The bigger MNPs often exhibited higher apparent recoveries owing to enhanced dye adsorption and aggregation. The fluorescence responses of labeled MNPs aligned with these trends and served as an internal validation of staining efficacy, especially in intricate matrices where apple juice displayed significant autofluorescence, necessitating pretreatment (e.g., dilution and/or centrifugation) to enhance the signal-to-background ratio. In all matrices, chemical digestion and filtration resulted in significant reductions in fluorescence intensity for both size categories, consistent with DLS, NTA, and SEM findings on particle removal or aggregation. The integrated Nile Red-based method is effective for monitoring both non-labeled MNPs in the test solutions although more research is still needed for improvement of recovery rate and detection sensitivity. These findings will be useful for creating a cohesive analytical and filtering platform to determine MNP in diverse food systems. Furthermore, the integration of improved characterization techniques with novel filtration materials such as DCN and biochar presents interesting approaches for future detection and mitigation tactics in evaluation of dietary MNPs and assistance in advancement of advance the regulatory policies on health impacts of MNPs.University of Delaware, Department of Animal and Food SciencesM.S
Using liquid metal coils to harvest the body’s kinetic energy
No full textThis article was originally published in Engineering Research Express. The version of record is available at: https://doi.org/10.1088/2631-8695/ae3940
‘This is the Accepted Manuscript version of an article accepted for publication in Engineering Research Express . IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The Version of Record is available online at https://doi.org/10.1088/2631-8695/ae3940
This article will be embargoed until January 28, 2027Harvesting energy from human motion is a promising technique for powering wearable devices on the body. Achieving both significant amounts of power and comfort in the same system is however challenging; electromagnetic harvesters based on moving magnets are capable of generating sizeable amounts of power from the body’s motion but only at a significant cost in weight and discomfort in limiting practical use. In this paper we present a stretchable electromagnetic energy harvester based on a sliding magnet through coils made of the room temperature liquid metal eutectic gallium indium (EGaIn). The harvester is fabricated by injecting EGaIn into commercial silicone tubing wrapped around 3D printed preforms, with molded silicone used to hold the coils in place followed by removal from the preforms. The behavior of the liquid metal coils with a moving magnet was first modelled using an analytical model and compared with experimental testing using a sliding drop tower test to verify the electromagnetic characteristics for different velocities. A motorized shaker in the laboratory was then used to characterize the harvested energy during vibration, followed by testing on a person running on a treadmill. Strain testing also demonstrated that the harvester could operate up to 20% mechanical strain, sufficient for use in close contact with the body. The device generates a peak power of 160 μW and average power of 17 μW during the laboratory test, and 100 μW peak and 14 μW average for the wearable version on the treadmill, nearly an order of magnitude higher power than past on-body stretchable electromagnetic harvesters.This work was carried out with the support of the University of Delaware Research Foundation
Evaluation of selectively bred eastern oyster (Crassostrea virginica) strains in Delaware Bay: implications for living shoreline enhancement
No full textHale, Edward A.Oyster-based restoration projects, particularly living shorelines, are being installed to protect coastal ecosystems and infrastructure. While these installations often successfully create aquatic habitats, further refinement in optimizing the growth potential of shellfish on shoreline installations will increase the success rate and efficiency of restoration projects. This study evaluated the growth and mortality of two farmed strains of oyster, NEH® (high salinity tolerant) and DBX (medium and low salinity tolerant), in the lower Delaware Bay. From July to October 2023, we monitored the growth and mortality of each strain cultured in rack-and-bag oyster aquaculture gear positioned at intertidal and subtidal environments. The effect of tidal position, temperature, salinity, and dissolved oxygen on oyster performance (average oyster length and weekly oyster mortality) was examined using Generalized Additive Models (GAMs) to determine covariate importance towards the growth and survival of both oyster strains. Our findings indicate that NEH® oysters exhibited better meat condition than DBX oysters (two-way ANOVA, p = 0.03), as well as a significant difference in average weekly length (Growth GAM, p = 0.02). Oyster weekly average length was influenced by average temperature and previous week’s minimum dissolved oxygen, while weekly mortality was influenced by minimum and average salinity and minimum dissolved oxygen. Subtidal oysters exhibited greater growth (Growth GAM, p < 0.001) and survival (Mortality GAM, p = 0.01; Scheirer-Ray-Hare test, p < 0.001; Wilcoxon rank-sum test, p < 0.001, adjusted with Bonferroni corrections) than intertidal oysters, suggesting the addition of subtidal design features can enhance the likelihood of success for oyster restoration projects. These results emphasize the need to select an appropriate strain based on local environmental conditions and suggest that pre-seeding selectively bred oysters into living shoreline materials is a viable option to enhance restoration efficiency. Our results aid in our understanding of identifying important physical and environmental factors that determine oyster performance and provide insights via statistical models that can be applied to inform restoration and shellfish-based living shoreline planning.University of Delaware, School of Marine Science and PolicyM.S
Approach Motivation and Reward Sensitivity: Effects ofHigh-Definition Transcranial Direct Current Stimulation(HD-tDCS) to Brain Hemispheres on Effort-Related Cardiovascular Response
No full textThis article was originally published in European Journal of Neuroscience. The version of record is available at: https://doi.org/10.1111/ejn.70404
This is an open access article under the terms of the Creative Commons Attribution License, (https://creativecommons.org/licenses/by/4.0/) which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
© 2026 The Author(s). European Journal of Neuroscience published by Federation of European Neuroscience Societies and John Wiley & SonsThis study examined the effect of brain hemisphere stimulation on effort intensity. We applied high‐definition transcranial direct current stimulation (HD‐tDCS) to the dorsolateral prefrontal cortex (dlPFC) to manipulate left or right hemispheric activity and assess its impact on cardiovascular responses reflecting effort. In total, 102 participants (65 women, 37 men) performed a mental concentration task under right cathodal, left cathodal, or sham stimulation conditions. We recorded cardiovascular responses, including pre‐ejection period (PEP), systolic blood pressure (SBP), heart rate (HR), and diastolic blood pressure (DBP). Preregistered hypotheses predicted right cathodal stimulation to lead to greater left frontal hemispheric activity. This should result in higher effort during a mental concentration task of unclear difficulty by increasing approach motivation and thus success importance. As predicted, right cathodal stimulation increased PEP and SBP reactivity, indicating higher effort compared to the left cathodal and sham stimulation conditions. However, this effect was only evident in women, with men exhibiting a contrasting pattern. Our findings highlight the sex‐specific effects of brain stimulation on cardiovascular responses reflecting effort, with the anticipated effects appearing in women.This research was supported by an Ambizione grant from the Swiss National Science Foundation (SNF PZ00P1_216471), awarded to Dr.David Framorando. We thank Sarah Delobel for her assistance as ahired experimenter. Open access publishing facilitated by Universite deGeneve, as part of the Wiley - Universite de Geneve agreement via the Consortium Of Swiss Academic Libraries
Modular parallel plate flow chamber with tunable substrate mechanics and defined shear stress
No full textThis article was originally published in Biomedical Microdevices The version of record is available at: https://doi.org/10.1007/s10544-025-00787-6
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.Cells integrate multiple mechanical cues simultaneously, yet most in vitro models examine extracellular matrix (ECM) stiffness and fluid shear stress (FSS) in isolation, limiting our understanding of mechanotransduction. We developed a parallel plate flow chamber with a polyacrylamide (PAA) substratum enabling independent, tunable control of substrate stiffness and FSS using readily available materials. We confirm that the PAA substratum has controllable mechanical prop-erties that support the growth of Madin-Darby canine kidney epithelial cells across a range of stiffnesses. Furthermore, the flow chamber design accommodates the volumetric equilibrium swelling of the gel, maintaining a predictable fluid channel height that allows for the application of controlled fluid shear stress to cells within the device, confirmed through particle image velocimetry of perfused microspheres. Single flow chambers support the growth of sufficient cellular numbers for endpoint analyses, such as Western blots. Finally, quantitative analysis of F-actin organization revealed that substrate stiff-ness and FSS synergistically increase filament length with independent effects on filament width, demonstrating the ability and usefulness of this model as a tool for studying the effect of multiple concurrent forces on cell behavior.The authors thank Katherine M. Nelson, Ph.D., for reviewing and commenting on the manuscript. This work was supported in part by grants from the National Institutes of Health: R01DE029655 and R01HL145147. Microscopy equipment was acquired with a shared instrumentation grant (S10 OD030321) and access was supported by NIH-NIGMS (P20 GM103446, P20 GM139760) and the State of Delaware. The BioRxiv template was adapted from the Henriques lab
